devil is in details, and apple excels in details.

Not just check the spec, not just check the home screen (Samsung copies Apple UI anyway), try something hard to get it right. Like try to pinch-zoom the map in its map application, try to scroll/zoom a complicate website (like wenxuecity.com ;) ) in its browser.

Also try some hot applications, like facebook/twitter/tumblr clients on both platform, see what is the difference.

I think Android (including Samsung Galaxy S3) still lags behind iOS (iPhone/iPad).